<html xmlns="http://www.w3.org/1999/xhtml" xmlns:m="http://www.w3.org/1998/Math/MathML">
<head>
<style type="text/css">

[class="wide"] { width: 100000000px }

</style>
<script type="text/javascript">

function boom()
{
  document.getElementById("targ").appendChild(document.getElementById("cm").cloneNode(true)); 
}

</script>
</head>

<body onload="boom();">
<table>
  <tbody>
    <td><m:mrow class="wide" id="cm"></m:mrow></td>
    <tr><m:mrow id="targ"></m:mrow></tr>
  </tbody>
</table>
</body>

</html>
